Binary adaptive optics: atmospheric wave-front correction with a half-wave phase shifter.

We describe a binary approach to adaptive wave-front correction, especially suitable for narrow band applications, which would be simpler than conventional adaptive technology. Appropriate parts of the aberrant wave front are phase retarded by half a wavelength to ensure that none of the image-forming rays add together destructively. Simulations for monochromatic light show that the residual wave-front errors, in the absence of other errors, would result in Strehl ratios of ~40% with diffraction-limited widths at visible wavelengths.

Validation of interferometric imaging from a pupil-masking experiment on a solar telescope.

We present the results of a pupil-masking experiment that uses the Sun as the source object. The goal of our experiment was a proof-of-concept validation for a Fizeau (image-plane) interferometric beam combination with a complex source that overfilled the field of view. We employed a phase-diversity technique to measure the optical phases required to recover the instantaneous optical transfer function for the masked pupil.

Wave-front sensing and image deconvolution of solar data.

High spatial resolution is of the utmost importance for understanding the phenomena that are present on the solar surface. Several techniques for wave-front sensing and image reconstruction have been proposed and used with varying degrees of success. The results of a wave-front sensing and imagereconstruction experiment that uses phase information obtained by comparing in-focus and out-of-focus images are presented.